Vascular leak is characterized by hypotension, peripheral edema, and hypoalbuminemia. Vascular leak can occur as a side effect of illness especially illnesses due to pathogens, inter alia, viruses and bacteria. Vascular leak complicates the healing process and can itself be a direct result of certain therapies. For example, patients suffering from malignant renal carcinoma are given Interleukin-2 to help boost their immune system; however, this treatment must be withdrawn in many patients due to the onset of severe vascular leak well before the full course of treatment can be administered. Therefore, the cancer treatment is withdrawn earlier than desired and usually before the therapy is maximally effective. VLS restricts the doses of IL-2 which can be administered to humans and, in some cases, necessitates the cessation of therapy.
VLS is characterized by an increase in vascular permeability accompanied by extravasation of fluids and proteins resulting in interstitial edema and organ failure. Manifestations of VLS include fluid retention, increase in body weight, peripheral edema, pleural and pericardial effusions, ascites, anasarca and, in severe form, signs of pulmonary and cardiovascular failure. Symptoms are highly variable among patients and the causes are poorly understood. Endothelial cell modifications or damage are thought to be important is vascular leak. The pathogenesis of endothelial cell (EC) damage is complex and can involve activation or damage to ECs and leukocytes, release of cytokines and of inflammatory mediators, alteration in cell-cell and cell-matrix adhesion and in cytoskeleton function.
During the course of antiviral and antibacterial infections, patients can develop vascular leak that is induced as result of the initial infection. There is now a long felt need for a method of preventing vascular leak due to viral or bacterial infection, and therefore provide a method of increasing the survival of humans or other mammals infected with one or more pathogens. In addition, there is a long felt need for a method of preventing vascular leakage due to certain anticancer drugs or other anticancer therapies such that the administration of anticancer drugs or anticancer therapies can be given to humans or other mammals for a longer course of treatment or therapy.